Brett McGurk is a CNN global affairs analyst who served in senior national security positions under Presidents George W. Bush, Barack Obama, Donald Trump and Joe Biden.
Shortly after I landed in Baghdad for the first time in January 2004, US intelligence services intercepted a letter from Ayman al-Zawahiri, Osama bin Laden’s deputy, to Abu Musab al-Zarqawi, the leader of al Qaeda in Iraq. The letter discussed the use of ruthless violence to establish an Islamic caliphate— first inside Iraq and ultimately across the broader Middle East.
“The greatest battle of Islam in this era is now being waged,” Zawahiri wrote.
The United States publicized the letter, but few took seriously the idea that al Qaeda could carve out and govern territory across the heart of the Arab world.
Ten years later, I was back in Baghdad as Zarqawi’s successor, Abu Bakr al-Baghdadi, conquered Iraq’s second-largest city and declared a caliphate spanning territory the size of Indiana with millions living under its rule. We spent the next decade dismantling it.
